A wind turbine comprises a rotor having one or more rotor blades connected to the rotor and being supported by a bearing. Further, the rotor is mechanically connected to a generator to generate electric energy from the mechanical rotational energy. The mechanical bearing supporting the rotor is subjected to stress and mechanical loads during operation. Thereby, a key factor in determining the life time of the mechanical bearing is the amplitude and direction of the forces acting on the bearing and the number of rotations travelled at a given load situation. The forces acting on the bearing may include radial and axial forces and bending moments or a combination of these forces.
In order to withstand the high loads acting on the bearings the bearings have been designed and sized for withstanding the highest loads expected during operation of the wind turbine. Thereby, the bearings become heavy and expensive.
There may be a need for a method and a generator control system for controlling a generator, in particular a generator of a wind turbine, wherein the loads acting on a bearing are reduced compared to a conventional system or method. Further, there may be a need for a method and a generator control system for controlling a generator, which enables to reduce the weight or size or costs of the bearing supporting the rotor. Further, there may be a need for a method and a generator control system for controlling a generator, wherein operating conditions, such as loads, noise emissions or stress and efficiency are improved compared to conventional systems or methods.
This need may be met by the subject matter according to the independent claims. Advantageous embodiments of the present invention are described by the dependent claims.